Merge git://git.kernel.org/pub/scm/gitk/gitk
[git/mjg.git] / builtin / diff.c
blob717fa1a3414e18cbdd4c6eb1e0785761687688d7
1 /*
2 * Builtin "git diff"
4 * Copyright (c) 2006 Junio C Hamano
5 */
6 #include "cache.h"
7 #include "color.h"
8 #include "commit.h"
9 #include "blob.h"
10 #include "tag.h"
11 #include "diff.h"
12 #include "diffcore.h"
13 #include "revision.h"
14 #include "log-tree.h"
15 #include "builtin.h"
16 #include "submodule.h"
18 struct blobinfo {
19 unsigned char sha1[20];
20 const char *name;
21 unsigned mode;
24 static const char builtin_diff_usage[] =
25 "git diff [<options>] [<commit> [<commit>]] [--] [<path>...]";
27 static void stuff_change(struct diff_options *opt,
28 unsigned old_mode, unsigned new_mode,
29 const unsigned char *old_sha1,
30 const unsigned char *new_sha1,
31 const char *old_name,
32 const char *new_name)
34 struct diff_filespec *one, *two;
36 if (!is_null_sha1(old_sha1) && !is_null_sha1(new_sha1) &&
37 !hashcmp(old_sha1, new_sha1) && (old_mode == new_mode))
38 return;
40 if (DIFF_OPT_TST(opt, REVERSE_DIFF)) {
41 unsigned tmp;
42 const unsigned char *tmp_u;
43 const char *tmp_c;
44 tmp = old_mode; old_mode = new_mode; new_mode = tmp;
45 tmp_u = old_sha1; old_sha1 = new_sha1; new_sha1 = tmp_u;
46 tmp_c = old_name; old_name = new_name; new_name = tmp_c;
49 if (opt->prefix &&
50 (strncmp(old_name, opt->prefix, opt->prefix_length) ||
51 strncmp(new_name, opt->prefix, opt->prefix_length)))
52 return;
54 one = alloc_filespec(old_name);
55 two = alloc_filespec(new_name);
56 fill_filespec(one, old_sha1, old_mode);
57 fill_filespec(two, new_sha1, new_mode);
59 diff_queue(&diff_queued_diff, one, two);
62 static int builtin_diff_b_f(struct rev_info *revs,
63 int argc, const char **argv,
64 struct blobinfo *blob,
65 const char *path)
67 /* Blob vs file in the working tree*/
68 struct stat st;
70 if (argc > 1)
71 usage(builtin_diff_usage);
73 if (lstat(path, &st))
74 die_errno(_("failed to stat '%s'"), path);
75 if (!(S_ISREG(st.st_mode) || S_ISLNK(st.st_mode)))
76 die(_("'%s': not a regular file or symlink"), path);
78 diff_set_mnemonic_prefix(&revs->diffopt, "o/", "w/");
80 if (blob[0].mode == S_IFINVALID)
81 blob[0].mode = canon_mode(st.st_mode);
83 stuff_change(&revs->diffopt,
84 blob[0].mode, canon_mode(st.st_mode),
85 blob[0].sha1, null_sha1,
86 path, path);
87 diffcore_std(&revs->diffopt);
88 diff_flush(&revs->diffopt);
89 return 0;
92 static int builtin_diff_blobs(struct rev_info *revs,
93 int argc, const char **argv,
94 struct blobinfo *blob)
96 unsigned mode = canon_mode(S_IFREG | 0644);
98 if (argc > 1)
99 usage(builtin_diff_usage);
101 if (blob[0].mode == S_IFINVALID)
102 blob[0].mode = mode;
104 if (blob[1].mode == S_IFINVALID)
105 blob[1].mode = mode;
107 stuff_change(&revs->diffopt,
108 blob[0].mode, blob[1].mode,
109 blob[0].sha1, blob[1].sha1,
110 blob[0].name, blob[1].name);
111 diffcore_std(&revs->diffopt);
112 diff_flush(&revs->diffopt);
113 return 0;
116 static int builtin_diff_index(struct rev_info *revs,
117 int argc, const char **argv)
119 int cached = 0;
120 while (1 < argc) {
121 const char *arg = argv[1];
122 if (!strcmp(arg, "--cached") || !strcmp(arg, "--staged"))
123 cached = 1;
124 else
125 usage(builtin_diff_usage);
126 argv++; argc--;
128 if (!cached)
129 setup_work_tree();
131 * Make sure there is one revision (i.e. pending object),
132 * and there is no revision filtering parameters.
134 if (revs->pending.nr != 1 ||
135 revs->max_count != -1 || revs->min_age != -1 ||
136 revs->max_age != -1)
137 usage(builtin_diff_usage);
138 if (read_cache_preload(revs->diffopt.pathspec.raw) < 0) {
139 perror("read_cache_preload");
140 return -1;
142 return run_diff_index(revs, cached);
145 static int builtin_diff_tree(struct rev_info *revs,
146 int argc, const char **argv,
147 struct object_array_entry *ent)
149 const unsigned char *(sha1[2]);
150 int swap = 0;
152 if (argc > 1)
153 usage(builtin_diff_usage);
155 /* We saw two trees, ent[0] and ent[1].
156 * if ent[1] is uninteresting, they are swapped
158 if (ent[1].item->flags & UNINTERESTING)
159 swap = 1;
160 sha1[swap] = ent[0].item->sha1;
161 sha1[1-swap] = ent[1].item->sha1;
162 diff_tree_sha1(sha1[0], sha1[1], "", &revs->diffopt);
163 log_tree_diff_flush(revs);
164 return 0;
167 static int builtin_diff_combined(struct rev_info *revs,
168 int argc, const char **argv,
169 struct object_array_entry *ent,
170 int ents)
172 const unsigned char (*parent)[20];
173 int i;
175 if (argc > 1)
176 usage(builtin_diff_usage);
178 if (!revs->dense_combined_merges && !revs->combine_merges)
179 revs->dense_combined_merges = revs->combine_merges = 1;
180 parent = xmalloc(ents * sizeof(*parent));
181 for (i = 0; i < ents; i++)
182 hashcpy((unsigned char *)(parent + i), ent[i].item->sha1);
183 diff_tree_combined(parent[0], parent + 1, ents - 1,
184 revs->dense_combined_merges, revs);
185 return 0;
188 static void refresh_index_quietly(void)
190 struct lock_file *lock_file;
191 int fd;
193 lock_file = xcalloc(1, sizeof(struct lock_file));
194 fd = hold_locked_index(lock_file, 0);
195 if (fd < 0)
196 return;
197 discard_cache();
198 read_cache();
199 refresh_cache(REFRESH_QUIET|REFRESH_UNMERGED);
200 update_index_if_able(&the_index, lock_file);
203 static int builtin_diff_files(struct rev_info *revs, int argc, const char **argv)
205 int result;
206 unsigned int options = 0;
208 while (1 < argc && argv[1][0] == '-') {
209 if (!strcmp(argv[1], "--base"))
210 revs->max_count = 1;
211 else if (!strcmp(argv[1], "--ours"))
212 revs->max_count = 2;
213 else if (!strcmp(argv[1], "--theirs"))
214 revs->max_count = 3;
215 else if (!strcmp(argv[1], "-q"))
216 options |= DIFF_SILENT_ON_REMOVED;
217 else if (!strcmp(argv[1], "-h"))
218 usage(builtin_diff_usage);
219 else
220 return error(_("invalid option: %s"), argv[1]);
221 argv++; argc--;
225 * "diff --base" should not combine merges because it was not
226 * asked to. "diff -c" should not densify (if the user wants
227 * dense one, --cc can be explicitly asked for, or just rely
228 * on the default).
230 if (revs->max_count == -1 && !revs->combine_merges &&
231 (revs->diffopt.output_format & DIFF_FORMAT_PATCH))
232 revs->combine_merges = revs->dense_combined_merges = 1;
234 setup_work_tree();
235 if (read_cache_preload(revs->diffopt.pathspec.raw) < 0) {
236 perror("read_cache_preload");
237 return -1;
239 result = run_diff_files(revs, options);
240 return diff_result_code(&revs->diffopt, result);
243 int cmd_diff(int argc, const char **argv, const char *prefix)
245 int i;
246 struct rev_info rev;
247 struct object_array_entry ent[100];
248 int ents = 0, blobs = 0, paths = 0;
249 const char *path = NULL;
250 struct blobinfo blob[2];
251 int nongit;
252 int result = 0;
255 * We could get N tree-ish in the rev.pending_objects list.
256 * Also there could be M blobs there, and P pathspecs.
258 * N=0, M=0:
259 * cache vs files (diff-files)
260 * N=0, M=2:
261 * compare two random blobs. P must be zero.
262 * N=0, M=1, P=1:
263 * compare a blob with a working tree file.
265 * N=1, M=0:
266 * tree vs cache (diff-index --cached)
268 * N=2, M=0:
269 * tree vs tree (diff-tree)
271 * N=0, M=0, P=2:
272 * compare two filesystem entities (aka --no-index).
274 * Other cases are errors.
277 prefix = setup_git_directory_gently(&nongit);
278 gitmodules_config();
279 git_config(git_diff_ui_config, NULL);
281 if (diff_use_color_default == -1)
282 diff_use_color_default = git_use_color_default;
284 init_revisions(&rev, prefix);
286 /* If this is a no-index diff, just run it and exit there. */
287 diff_no_index(&rev, argc, argv, nongit, prefix);
289 /* Otherwise, we are doing the usual "git" diff */
290 rev.diffopt.skip_stat_unmatch = !!diff_auto_refresh_index;
292 /* Default to let external and textconv be used */
293 DIFF_OPT_SET(&rev.diffopt, ALLOW_EXTERNAL);
294 DIFF_OPT_SET(&rev.diffopt, ALLOW_TEXTCONV);
296 if (nongit)
297 die(_("Not a git repository"));
298 argc = setup_revisions(argc, argv, &rev, NULL);
299 if (!rev.diffopt.output_format) {
300 rev.diffopt.output_format = DIFF_FORMAT_PATCH;
301 if (diff_setup_done(&rev.diffopt) < 0)
302 die(_("diff_setup_done failed"));
305 DIFF_OPT_SET(&rev.diffopt, RECURSIVE);
308 * If the user asked for our exit code then don't start a
309 * pager or we would end up reporting its exit code instead.
311 if (!DIFF_OPT_TST(&rev.diffopt, EXIT_WITH_STATUS) &&
312 check_pager_config("diff") != 0)
313 setup_pager();
316 * Do we have --cached and not have a pending object, then
317 * default to HEAD by hand. Eek.
319 if (!rev.pending.nr) {
320 int i;
321 for (i = 1; i < argc; i++) {
322 const char *arg = argv[i];
323 if (!strcmp(arg, "--"))
324 break;
325 else if (!strcmp(arg, "--cached") ||
326 !strcmp(arg, "--staged")) {
327 add_head_to_pending(&rev);
328 if (!rev.pending.nr) {
329 struct tree *tree;
330 tree = lookup_tree((const unsigned char*)EMPTY_TREE_SHA1_BIN);
331 add_pending_object(&rev, &tree->object, "HEAD");
333 break;
338 for (i = 0; i < rev.pending.nr; i++) {
339 struct object_array_entry *list = rev.pending.objects+i;
340 struct object *obj = list->item;
341 const char *name = list->name;
342 int flags = (obj->flags & UNINTERESTING);
343 if (!obj->parsed)
344 obj = parse_object(obj->sha1);
345 obj = deref_tag(obj, NULL, 0);
346 if (!obj)
347 die(_("invalid object '%s' given."), name);
348 if (obj->type == OBJ_COMMIT)
349 obj = &((struct commit *)obj)->tree->object;
350 if (obj->type == OBJ_TREE) {
351 if (ARRAY_SIZE(ent) <= ents)
352 die(_("more than %d trees given: '%s'"),
353 (int) ARRAY_SIZE(ent), name);
354 obj->flags |= flags;
355 ent[ents].item = obj;
356 ent[ents].name = name;
357 ents++;
358 continue;
360 if (obj->type == OBJ_BLOB) {
361 if (2 <= blobs)
362 die(_("more than two blobs given: '%s'"), name);
363 hashcpy(blob[blobs].sha1, obj->sha1);
364 blob[blobs].name = name;
365 blob[blobs].mode = list->mode;
366 blobs++;
367 continue;
370 die(_("unhandled object '%s' given."), name);
372 if (rev.prune_data.nr) {
373 if (!path)
374 path = rev.prune_data.items[0].match;
375 paths += rev.prune_data.nr;
379 * Now, do the arguments look reasonable?
381 if (!ents) {
382 switch (blobs) {
383 case 0:
384 result = builtin_diff_files(&rev, argc, argv);
385 break;
386 case 1:
387 if (paths != 1)
388 usage(builtin_diff_usage);
389 result = builtin_diff_b_f(&rev, argc, argv, blob, path);
390 break;
391 case 2:
392 if (paths)
393 usage(builtin_diff_usage);
394 result = builtin_diff_blobs(&rev, argc, argv, blob);
395 break;
396 default:
397 usage(builtin_diff_usage);
400 else if (blobs)
401 usage(builtin_diff_usage);
402 else if (ents == 1)
403 result = builtin_diff_index(&rev, argc, argv);
404 else if (ents == 2)
405 result = builtin_diff_tree(&rev, argc, argv, ent);
406 else if (ent[0].item->flags & UNINTERESTING) {
408 * diff A...B where there is at least one merge base
409 * between A and B. We have ent[0] == merge-base,
410 * ent[ents-2] == A, and ent[ents-1] == B. Show diff
411 * between the base and B. Note that we pick one
412 * merge base at random if there are more than one.
414 ent[1] = ent[ents-1];
415 result = builtin_diff_tree(&rev, argc, argv, ent);
416 } else
417 result = builtin_diff_combined(&rev, argc, argv,
418 ent, ents);
419 result = diff_result_code(&rev.diffopt, result);
420 if (1 < rev.diffopt.skip_stat_unmatch)
421 refresh_index_quietly();
422 return result;